339 results about "Bismuth nitrate" patented technology

The invention discloses a method for preparing a bismuth ferrite composite catalytic material by using red mud as well as a product and application of the bismuth ferrite composite catalytic material. The method comprises the following steps: mixing chlorine salt and red mud, uniformly stirring, adding a hydrochloric acid solution, uniformly stirring, roasting, recovering flue gas generated in the roasting process, and obtaining roasting residues and roasting dust generated by recovering the flue gas after roasting is finished; and mixing the roasted dust and bismuth nitrate, uniformly stirring, adding the calcined residue, uniformly grinding, adding water, stirring, drying the material, and calcining to obtain the bismuth ferrite composite catalytic material. The preparation process is simple, the red mud is used as a main raw material, and full-amount resource utilization of the red mud can be achieved. The prepared composite catalytic material can be used for efficiently purifying landfill leachate, and COD, ammonia nitrogen, total phosphorus and heavy metal pollution are efficiently removed through a photocatalysis mechanism.

The invention provides a bismuth oxyhalide-bismuth oxysulfide in-situ heterojunction FT0 photoelectrode and a preparation method and application thereof, and belongs to the technical field of photoelectrochemistry. Bismuth nitrate pentahydrate serves as a raw material, bismuth oxyhalide crystals are formed on FTO through the reaction between halide and bismuth nitrate and in combination with an additive, bismuth oxyhalide-bismuth oxysulfide heterojunction is synthesized on the FTO through in-situ conversion by taking the bismuth oxyhalide crystals as a precursor, and the in-situ heterojunction photoelectrode with excellent photoelectric performance is prepared. A simple hot solvent method is adopted, operation is easy and convenient, low-cost raw materials are adopted, and the production cost is reduced. And meanwhile, in-situ conversion can enable a close-contact heterojunction interface to be formed between bismuth oxyhalide and bismuth oxysulfide, so that the response of an electrode to light is improved, the transfer of current-carrying electrons of the composite material is promoted, and the photoelectric property is greatly improved. And a new thought and method for in-situ synthesis of the heterojunction photoelectrode on the FTO is provided for the photoelectrochemical application industry.

The invention discloses nanoscale bismuth hydroxide as well as a preparation method and application thereof. The invention provides a preparation method of bismuth hydroxide. The preparation method comprises the following steps: reacting a mixture solution of a surfactant solution and a bismuth source solution at the temperature of 100-300 DEG C and the pressure of 0.5-5 MPa to obtain bismuth hydroxide, the pH value of the mixture liquid is 5-12; the bismuth source is bismuth nitrate; the surfactant is selected from polyvinylpyrrolidone or hexadecyl trimethyl ammonium bromide. According to the preparation method, bismuth hydroxide with the microscopic primary particle size of about 40-90 nm, uniform distribution, the secondary particle size D99 of 2-4 microns, the purity of 99.9% and the particle size of more than 99.9% can be obtained, and the adsorption rate of bismuth hydroxide to bromide ions and iodide ions reaches 80% or more.

The invention relates to the technical field of nano silver powder preparation, in particular to a preparation method of high-tap-density and high-purity silver powder. The problems that in the prior art, silver powder is insufficient in purity and low in tap density are solved. The method comprises the following steps: preparing silver nitrate into a solution, carrying out electrolytic pretreatment, and carrying out chemical reduction, coprecipitation and dissolution reduction to obtain a silver powder suspension; the silver powder suspension is subjected to physical vapor deposition, silver vapor is deposited on the surface of the silver powder under the action of argon, and silver powder particles are tightly arranged; preparing an electrolyte from silver nitrate and bismuth nitrate, and carrying out electrolytic refining; and finally, the high-tap-density high-purity silver powder is obtained through ultrasonic dispersion and supercritical fluid drying treatment. By strictly controlling the process sequence and parameters and utilizing the synergistic effect among the processes, impurities are effectively removed, the particle size distribution of nano silver powder particles is optimized, the purity and tap density of the nano silver powder are improved, and the application of the silver powder in conductive materials is optimized.

The invention discloses a high-dispersion graphene conductive adhesive solution for a battery and a preparation method of the high-dispersion graphene conductive adhesive solution, and belongs to the technical field of conductive adhesive solutions. The high-dispersion graphene conductive adhesive solution for the battery prepared by the invention is prepared from the following raw material components in parts by mass: 6 to 8 parts of high-dispersion graphene, 4.5 to 13.5 parts of an adhesive and 60 to 90 parts of a solvent, the preparation method comprises the following steps: ultrasonically dispersing graphene in a mixed solution of hexadecyl triyl ammonium bromide and deionized water, sequentially adding hexadecyl triyl ammonium bromide, sodium molybdate dehydrate, bismuth nitrate pentahydrate and cerium nitrate hexahydrate, uniformly stirring and dispersing, performing hydrothermal reaction, washing, drying, grinding and sieving to obtain the high-dispersion graphene. The adhesive is prepared from an amphiphilic polyethylene glycol-polycaprolactone block copolymer and amphiphilic polyacrylate.

The invention discloses a preparation method and application of a CuBi2O4 film electrode, and belongs to the field of film materials. The preparation method of the CuBi2O4 film electrode comprises the following steps: mixing an aqueous solution of 0.05 mol / L-0. 2 mol / L copper acetate and an aqueous solution of 0.05 mol / L-0. 2 mol / L sodium acetate to obtain an electrolyte I, and obtaining a Cu2O film on FTO (Fluorine-doped Tin Oxide) by adopting an electrodeposition method; adding a coordination agent, KOH and fused salt KNO3 into a 0.05 mol / L-0. 3 mol / L bismuth nitrate solution or adding water to dilute to obtain a solution II; and pulling and dipping the obtained Cu2O film in the solution II, carrying out annealing treatment, washing with deionized water, and drying to obtain the CuBi2O4 film electrode. According to the preparation method disclosed by the invention, Cu2O with uniform surface and good compactness is obtained by regulating and controlling the concentration ratio of cupric acetate to sodium acetate, and the high-quality CuBi2O4 film electrode is prepared by optimizing the concentrations of the coordination agent, the mineralizing agent and the fused salt on the basis.

The invention discloses a nitrogen-doped oxygen-vacancy-rich three-dimensional flower-shaped bismuth oxide electrocatalyst as well as a preparation method and application thereof, relates to the technical field of electrocatalysts, and solves the problems that a traditional bismuth oxide catalyst is insufficient in electron transfer capability and low in active site utilization rate. The preparation method comprises the following steps: dissolving bismuth nitrate, polyvinylpyrrolidone and sodium oleate in a mixed solvent of methanol and N, N-dimethylformamide, and stirring and dissolving to obtain a solution A; the preparation method comprises the following steps: dissolving 1, 3, 5-tri (4-carboxyl phenyl) benzene in a mixed solvent of methanol and N, N-dimethylformamide, and stirring and dissolving to obtain a solution B; and adding the B into the A, uniformly stirring, heating in an oil bath, reacting under magnetic stirring, cooling to room temperature, filtering, washing and drying the product to obtain white powder, calcining in a tubular furnace to obtain three-dimensional flower-shaped Bi2O3, putting in the tubular furnace, introducing argon, introducing ammonia gas, heating, and carrying out heat preservation reaction to obtain the electrocatalyst. The catalyst can be used for catalyzing nitrogen reduction synthesis ammonia reaction.

The invention provides an efficient environment-friendly petroleum passivator as well as a preparation method and application thereof, and belongs to the technical field of passivators. The preparation method comprises the following steps: reacting bismuth nitrate with tetra (4-carboxyl phenyl) porphyrin and benzoic acid to prepare a carboxyl phenyl porphyrin bismuth-MOF material, reacting antimony nitrate with tetra (4-pyridyl) porphyrin and benzoic acid to prepare a pyridyl porphyrin antimony-MOF material, and performing sol-gel reaction on lanthanum isopropoxide and cerium isopropoxide to prepare lanthanum-cerium sol; the preparation method comprises the following steps: mixing calcium nitrate, magnesium chloride, organic acid, organic amine and hydrogen peroxide for reaction to prepare a calcium / magnesium organic matter, mixing the calcium / magnesium organic matter with other substances, adding the mixture into an acetonitrile / ethanol mixed solvent, and uniformly stirring and mixing to prepare the efficient environment-friendly petroleum passivator. The high-efficiency environment-friendly petroleum passivator prepared by the invention is green, safe, non-toxic and efficient, has better capturing and passivating effects on metal ions such as nickel and vanadium in the catalytic cracking reaction process of heavy oil, improves the activity of a catalyst, prolongs the service life of the catalyst, and thus, has a wide application prospect.

The invention belongs to the technical field of photocatalytic materials, and particularly relates to a manganese ferrite / bismuth tungstate heterojunction photocatalyst as well as a preparation method and application thereof. The preparation method comprises the following steps: 1) dissolving sodium tungstate dihydrate, bismuth nitrate pentahydrate and hexadecyl trimethyl ammonium bromide in deionized water, and obtaining bismuth tungstate by using a hydrothermal method; 2) dissolving ferric chloride hexahydrate and manganese chloride tetrahydrate in water, then adding a sodium hydroxide solution, and obtaining manganese ferrite by using a hydrothermal method; and 3) dissolving bismuth tungstate and manganese ferrite into a sodium hydroxide solution, stirring, and drying to obtain the manganese ferrite / bismuth tungstate heterojunction photocatalyst. The formation of the heterojunction can greatly improve the activity of the manganese ferrite / bismuth tungstate in photocatalytic reduction of carbon dioxide.

The invention discloses an in-situ synthesized halogen-modified bismuth nano electro-catalysis electrode and a preparation method and application thereof.The preparation method comprises the steps that basic bismuth nitrate is prepared through a simple hydrolysis method, then halogen atoms are grafted on the surface of the basic bismuth nitrate through water bath treatment, and a precursor is synthesized; and then the halogen atom modified bismuth-based nano electro-catalysis electrode is formed through in-situ reduction under an ECR (Electron Cyclotron Resonance) condition. The preparation method is simple and convenient, the reaction is relatively mild, the energy consumption is low, and the prepared halogen-modified bismuth nano catalytic material can effectively inhibit the competitive reaction of hydrogen evolution and improve the current density, so that the halogen-modified bismuth nano catalytic material shows relatively good performance of electrocatalytically reducing carbon dioxide into formic acid.

The invention relates to a preparation method of oxygen vacancy-containing bismuth vanadate BiVO4-OVs or metal bismuth-loaded bismuth vanadate xBi0 / BiVO4. The preparation method comprises the following steps: weighing bismuth nitrate pentahydrate and ammonium metavanadate according to a molar ratio of bismuth nitrate pentahydrate to ammonium metavanadate of 1: 1 + x; the preparation method comprises the following steps: respectively dissolving bismuth nitrate pentahydrate and ammonium metavanadate in a solvent, fully mixing the bismuth nitrate pentahydrate and the ammonium metavanadate, adjusting the pH value of the solution, placing a reaction system in an environment of 140-180 DEG C for reaction, washing and drying a product, and roasting under the protection of argon to obtain the product. In addition, the invention also discloses an application of the bismuth vanadate BiVO4-OVs containing oxygen vacancies or the bismuth vanadate xBi0 / BiVO4 loaded with metal bismuth as a catalyst in preparation of benzaldehyde by photocatalytic oxygen oxidation of cinnamyl aldehyde. According to the method, the utilization rate of cinnamyl aldehyde can be increased, efficient oxidation can be achieved in the initial stage of reaction, good benzaldehyde selectivity can be achieved, and the adopted catalyst is efficient and non-toxic and has no influence on the naturalness of benzaldehyde.

The invention belongs to the technical field of photocatalytic materials, and particularly relates to a graphite-phase carbon nitride / iron-doped bismuth oxychloride heterojunction photocatalyst as well as a preparation method and application thereof. The preparation method comprises the following steps: firstly, putting urea into a crucible with a cover, and calcining in air by utilizing a thermal polymerization method to obtain graphite-phase carbon nitride; then uniformly dispersing the graphite phase carbon nitride into a mannitol solution in which bismuth nitrate pentahydrate is dissolved, then adding ferric nitrate nonahydrate and potassium chloride into the solution, and obtaining the graphite phase carbon nitride / iron-doped bismuth oxychloride heterojunction photocatalyst by utilizing a hydrothermal method. The formation of the heterojunction can greatly improve the activity of the graphite-phase carbon nitride in photocatalytic reduction of carbon dioxide.

The present invention discloses a method for preparing a glass fiber diaphragm modified with a bismuth-based metal organic framework material, comprising: (1) using bismuth nitrate pentahydrate and trimesic acid as raw materials, and synthesizing a bismuth-based metal organic framework material by solvent thermal reaction; (2) adding the bismuth-based metal organic framework material prepared in step (1) and polyvinylidene fluoride to an N-methylpyrrolidone solution for mixing; (3) modifying the mixed solution obtained in step (2) onto a glass fiber diaphragm by a suction filtration method, and obtaining a glass fiber diaphragm modified with a bismuth-based metal organic framework material after drying. The present invention also discloses a glass fiber diaphragm modified with a bismuth-based metal organic framework material obtained by the above-mentioned preparation method and its application in a zinc ion battery. The glass fiber diaphragm modified with a bismuth-based metal organic framework material provided by the present invention can improve its electrochemical performance when applied to a zinc ion battery, thereby solving the problem of poor cycle performance of ordinary glass fiber diaphragms applied to aqueous batteries.

The invention discloses a strontium-doped bismuth titanate-based ferroelectric film and a preparation method thereof, and belongs to the technical field of dielectric energy storage materials. The chemical composition of the film is Ba < 1-x > Sr < x > Bi < 4 > Ti < 4 > O < 15 >, wherein x ranges from 0.025 to 0.1. The preparation method comprises the following steps: mixing ethylene glycol monomethyl ether and ethylene glycol, adding bismuth nitrate, barium acetate, strontium acetate and butyl titanate, fully stirring and filtering to obtain a precursor solution, aging, dripping to the center of a substrate for spin coating, heating a spin-coated sample to obtain a dry film, and annealing to obtain the ferroelectric film. The method is low in technological condition requirement, and the thin film obtains the optimal energy storage density by changing the doping proportion of Sr. According to the ferroelectric film, when x is equal to 0.075, the leakage current density of Ba0. 925Sr0. 075Bi4Ti4O15 (BBST75) is only 1.59 * 10 <-7 > A / cm < 2 >, the breakdown field strength is as high as 3.22 MV / cm, and at the moment, the film has the energy storage density of 28.2 J / cm < 3 > and the energy storage efficiency of 80.36%.

The invention discloses a preparation method of a beaded cobalt-doped Bi25FeO40 / BiFeO3 nanofiber wave-absorbing material, which comprises the following steps: obtaining a precursor by a standing method, and adding the precursor, bismuth nitrate, ferric nitrate and a spinning aid into a mixed solvent compounded by N, N-dimethylformamide and absolute ethyl alcohol to obtain a spinning solution; spinning the spinning solution by adopting an electrostatic spinning technology to obtain a nanofiber membrane; and finally, drying and calcining to obtain the wave-absorbing material. According to the wave-absorbing material, multiple reflection and scattering of electromagnetic waves are increased, the absorption performance of the electromagnetic waves is improved, due to the fact that a heterogeneous interface is generated after two phases are compounded, the interface polarization loss is further increased, when the thickness of the wave-absorbing material is 2.33 mm, the minimum reflection loss reaches-56.01 dB, the effective absorption frequency band width is 6.32 GHz, and the whole Ku wave band is covered.

The invention relates to a preparation method and application of a bismuth oxysulfide-hydrogel-melamine photo-thermal evaporator imitating a'sun cloth structure ', dithiothreitol and bismuth nitrate are dissolved in an organic solvent, a surfactant ligand is added, then a sodium hydroxide aqueous solution is added, after the reaction is finished, centrifugation, washing and drying are performed, and crystalline two-dimensional bismuth oxysulfide nanosheets are obtained; the preparation method comprises the following steps: adding bismuth oxysulfide nanosheets into a polyvinyl alcohol aqueous solution and glutaraldehyde, uniformly stirring, continuously adding a hydrochloric acid solution, continuously uniformly stirring to obtain a mixed liquid, pouring the mixed liquid onto a melamine foam skeleton, gelatinizing, freezing, drying, washing, and finally freeze-drying to obtain the 3D bismuth oxysulfide-hydrogel-melamine evaporator. The method has the advantages that the process is simple, the cost is low, by combining the photo-thermal conversion performance of bismuth oxysulfide and the unique sun-imitating cloth structural design, the sunlight capturing and conversion efficiency is improved, and efficient and stable solar photo-thermal seawater evaporation can be achieved.

The invention relates to a preparation method of a bismuth ferrite-based composite material. The invention aims to solve the problems of poor conductivity and few active sites of the existing bismuth ferrite electrode material, and provides a preparation method of an efficient electro-catalytic hydrogen evolution catalyst. According to the method, bismuth nitrate, ferric chloride, ethylene glycol, ammonia water, sodium hydroxide, thiourea, ammonium molybdate and cobalt nitrate are used as raw materials, a two-step hydrothermal method is adopted, the bismuth ferrite-based cobalt-doped molybdenum disulfide composite material is prepared, and the preparation method is provided for improving the electro-catalytic hydrogen evolution performance of existing bismuth ferrite.

The invention discloses a preparation method of a catalyst for synthesizing pyridine base, which comprises the following steps: mixing bismuth nitrate pentahydrate, cobalt nitrate hexahydrate and cadmium nitrate tetrahydrate to prepare a deionized water solution, regulating the pH value to 5 with nitric acid, dipping an H-ZSM-5 zeolite molecular sieve in a salt solution, continuously stirring, preserving heat, naturally cooling, washing, drying, and calcining at high temperature to obtain the catalyst for synthesizing pyridine base. And uniformly mixing the modified molecular sieve with the binder of the remaining components, carrying out spray drying, continuing high-temperature calcination, filling the formed catalyst into a fluidized bed reactor, and carrying out activity evaluation by adopting an aldehyde ammonia condensation process. According to the method, the novel catalyst is prepared by loading bismuth, cobalt, cadmium or other metal oxides on the ZSM-5 type zeolite molecular sieve, the reaction is carried out under the aldehyde ammonia synthesis process condition, the yield of pyridine in the pyridine base is increased, the yield ratio of pyridine to 3-methylpyridine can be increased to 20: 1, and the total yield of the pyridine base is kept to be 91.7% or above.

The invention relates to an iron oxide / bismuth vanadate composite photocatalytic material as well as a preparation method and application thereof in photocatalytic degradation of organic pollutants. The preparation method comprises the following steps: preparing a bismuth vanadate precursor by taking bismuth nitrate pentahydrate and ammonium metavanadate as raw materials; preparing bismuth vanadate by taking the bismuth vanadate precursor as a raw material and adopting a hydrothermal method; the bismuth vanadate is used as a substrate material, ferric chloride hexahydrate is used as an iron source, potassium iodate is used as an electron acceptor, a photodeposition method is adopted, iron oxide formed after Fe < 3 + > oxidation is selectively deposited on a {110} surface of the bismuth vanadate, and the iron oxide / bismuth vanadate composite photocatalytic material is obtained. The preparation method is simple and convenient to operate. The prepared iron oxide / bismuth vanadate composite photocatalytic material has proper forbidden bandwidth and good charge separation performance, effectively improves the photocatalytic activity, has a more excellent carbamazepine degradation effect compared with pure-phase BiVO4, and has a great application prospect in the aspect of degradation of antibiotic wastewater.

The invention relates to the technical field of composite photocatalysts, in particular to a nitrogen defect type carbon nitride quantum dot / bismuth defect type bismuth oxybromide heterojunction and a preparation method and application thereof.The preparation method includes the steps that urea and sodium citrate are heated, washed, centrifuged, frozen and dried to obtain nitrogen defect type carbon nitride quantum dots; dissolving nitrogen defect type carbon nitride quantum dots in ethylene glycol to obtain a first solution; adding bismuth nitrate pentahydrate into the first solution to obtain a second solution; dissolving a template agent in a mixed solution of ammonia water and deionized water to obtain a third solution; adding the third solution into the second solution, and carrying out hydrothermal reaction to obtain a second reaction product; and washing and centrifuging the second reaction product, and freeze-drying to obtain the nitrogen defect type carbon nitride quantum dot / bismuth defect type bismuth oxybromide heterojunction. The synthesized nitrogen defect type carbon nitride quantum dot / bismuth defect type bismuth oxybromide heterojunction has a remarkable effect in the aspect of photocatalytic reduction of CO2 into CO, and has the advantages of high light utilization rate and high electron hole pair separation rate.

The invention relates to the technical field of electrocatalytic reduction of carbon dioxide, and provides a water-phase ultrafast green preparation method of a bismuth-based metal organic framework, and the preparation method of the bismuth-based metal organic framework material comprises the following steps: taking bismuth nitrate pentahydrate as a bismuth source, taking trimesic acid as a ligand, and preparing the bismuth-based metal organic framework material through a surfactant-mediated sonochemistry method. A complex topological bismuth-based metal organic framework (CAU-17) is synthesized in water under an environmental condition. The synthesis method is rapid, environmentally friendly, low in cost and easy to operate, cetyltrimethylammonium bromide (CTAB) amphiphilic molecules are used as a structure inducer, removal (dehydration) of non-coordinated water is controlled, the deprotonation degree of ligands is improved, therefore, coordination and crystallization in an aqueous solution are adjusted, and by adjusting the dosage of the added CTAB, the deprotonation degree of the ligands is increased. And the crystal structure evolution from a preferentially generated compact sheet structure to a porous rod-shaped structure is realized. Meanwhile, the synthesized CAU-17 catalyst shows relatively high current density and Faraday efficiency in electrocatalytic reduction of carbon dioxide into formic acid, and has relatively good selectivity.

The invention belongs to the technical field of electrocatalytic reduction of CO2, and provides a Bi-based composite catalyst based on ZIF-67 as well as a preparation method and application of the Bi-based composite catalyst. The preparation method comprises the following steps: mixing 2-methylimidazole and methanol to obtain a methanol solution of 2-methylimidazole, and mixing cobalt nitrate and methanol to obtain a methanol solution of cobalt nitrate; the preparation method comprises the following steps: reacting a methanol solution of 2-methylimidazole with a methanol solution of cobalt nitrate to obtain ZIF-67; the preparation method comprises the following steps: mixing ZIF-67, methanol and an acid solution to obtain ZIF-67K; the preparation method comprises the following steps: reacting ZIF-67K, bismuth nitrate and water to obtain Bi-ZIF-67K; and the Bi-ZIF-67K is subjected to calcination. The ZIF-67 is used for providing a framework, so that the stability of the catalyst is improved, and the service life is prolonged; the ZIF-67 provides metal contact sites after being etched, active sites of Bi are exposed through calcination, and the activity, Faraday efficiency and selectivity of the catalyst are improved.

The invention relates to the technical field of sewage treatment, and discloses a photocatalytic material and a preparation method and application thereof.The method comprises the following steps that bismuth nitrate pentahydrate and sodium bromide are added into a mannitol solution according to the molar ratio of 1: 1.5, and ultrasonic dispersion is conducted to form turbid liquid; adding arginine into the turbid liquid, wherein the molar ratio of the arginine to the bismuth nitrate pentahydrate is (0-2.5): 1; adjusting the pH value of the turbid liquid and stirring to obtain a precipitate; the precipitate is filtered, washed and dried, and the photocatalytic material nVBi-(110) BiOBr is obtained.By means of the photocatalytic material, the removal rate of hexavalent chromium in alkaline wastewater with the pH being 7-10 can still exceed 90% within a short time, the photocatalytic material shows excellent stability and reaction activity, the technical problem that hexavalent chromium is difficult to remove efficiently in the alkaline environment is successfully solved, and the photocatalytic material has good application prospects. The method has important environmental application value and popularization potential.

The invention discloses a yeast bionic BiVO4 composite photocatalytic material and a synthesis method and application thereof.The synthesis method comprises the steps that firstly, bismuth nitrate pentahydrate, sodium dodecyl benzene sulfonate, nitric acid, ammonium metavanadate and sodium hydroxide serve as raw materials, yeast is added at the same time, and a yeast / BiVO4 composite photocatalyst is prepared through a hydrothermal reaction; and the photocatalyst is used for photocatalytic degradation of 2, 4-dichlorophenol. A hydrothermal reaction method is used, and the synthesis process is simple; the yeast / BiVO4 composite material is of a spherical structure, and compared with a traditional nano-powder or random-form catalyst, the three-dimensional spherical photocatalyst has the main advantages that the three-dimensional spherical photocatalyst is derived from a unique physical structure and can bring chemical property improvement, so that the efficiency of photocatalytic degradation of 2, 4-dichlorophenol is improved.

The invention belongs to the technical field of all-vanadium redox flow battery electrodes, and particularly relates to a bismuth metal modified electrode, a preparation method, application and an all-vanadium redox flow battery. The preparation method comprises the following steps: dissolving a bismuth source in an organic solvent to prepare an impregnation liquid; soaking the polyacrylonitrile-based graphite felt in the impregnation liquid, taking out the polyacrylonitrile-based graphite felt, and drying the polyacrylonitrile-based graphite felt to obtain a bismuth-source-impregnated polyacrylonitrile-based graphite felt; and performing Joule thermal pulse discharge heating on the polyacrylonitrile-based graphite felt impregnated with the bismuth source, washing and drying to obtain the bismuth metal modified electrode. The voltage of Joule thermal pulse discharge heating is 24-36 V, and the current is 56-83 A. According to the preparation method, joule thermal equipment is adopted for pulse calcination, bismuth metal particles are generated on the surface of the polyacrylonitrile-based graphite felt in situ, and the problem that the metal particles are prone to agglomeration is solved. Meanwhile, when the bismuth source is bismuth nitrate, nitrogen doping is synchronously realized while active sites of bismuth metal particles are introduced, so that the hydrophilicity and the reaction activity of the polyacrylonitrile-based graphite felt electrode are improved.

The invention discloses a preparation method and application of a heterojunction catalyst based on a two-dimensional zinc porphyrin metal organic framework, and belongs to the field of photochemical energy conversion and photocatalytic degradation. The invention aims to solve the technical problems of high-quality preparation of the artificial photosynthetic photocatalytic composite material and how to effectively improve the photochemical energy conversion efficiency. The method comprises the following steps: 1, dissolving bismuth nitrate pentahydrate, sodium tungstate dihydrate and sodium dodecyl dimethyl benzene sulfonate in deionized water, fully stirring, and transferring the solution to a reaction kettle for hydrothermal reaction; cooling to room temperature, washing and drying to obtain bismuth tungstate solid powder; 2, adding bismuth tungstate and meso-tetra (4-carboxyl phenyl) porphin into a mixed solution of N, N-dimethylformamide and ethanol, carrying out ultrasonic treatment, and fully stirring to obtain a solution A; dissolving zinc nitrate hexahydrate, pyrazine and polyvinylpyrrolidone in a mixed solution of N, N-dimethylformamide and ethanol, and fully stirring to obtain a solution B; after the solution is fully dissolved, dropwise adding the solution B into the solution A under ultrasonic and stirring conditions, and then putting the beaker into an oil bath pan for heating; and cooling to room temperature, washing, and storing in an ethanol solution to obtain the Zn-MOF / Bi2WO6 heterojunction composite material.

The invention relates to a preparation method and application of an ultra-efficient nitrate-based free radical activation catalyst, and the preparation method comprises the following steps: S1, dissolving bismuth nitrate Bi (NO3) 3.5 H2O and polyvinylpyrrolidone (PVP) in a mannitol solution; s2, adding potassium bromide into the solution in the step S1, and performing ultrasonic treatment to form a white suspension; s3, transferring the suspension into a high-pressure reaction kettle for hydrothermal reaction; and S4, after the reaction is completed, cooling, centrifugally collecting precipitates, washing, and carrying out vacuum freeze drying to obtain the bismuth oxybromide BixOBr nanosheet catalyst. According to the application of the super-efficient nitrate-based free radical activation catalyst in degradation of organic pollutants, the bismuth oxybromide BixOBr nanosheet catalyst is added into a water body containing nitrate, the nitrate is activated to generate free radicals by utilizing the piezoelectric effect induced by photoinduced deformation of the photocatalyst under the condition that an external electric field and an oxidizing agent are not needed, and the degradation efficiency of the nitrate-based free radical activation catalyst is improved. Therefore, organic pollutants are degraded.

The application relates to a preparation method of a composite semiconductor photocatalyst and application thereof, and comprises the following steps: preparing g-C3N4 nanosheets; dispersing the prepared g-C3N4 nanosheets into methanol at a mass fraction of 10% to 70%, then adding 750 mg of trimesic acid and 150 mg of bismuth nitrate, and ultrasonic treating for 10 min to obtain a mixed suspension; transferring the mixed suspension into a microwave reaction kettle for reaction, the reaction temperature is 90 to 130 DEG C, the reaction time is 30 to 60 min, and centrifugal drying is carried out after the reaction is completed; then g-C3N4 / Bi-MOF is obtained through anhydrous methanol washing and freeze drying; a heterostructure is constructed, the energy band structure is changed, the charge transmission resistance is reduced, the photocatalytic activity is improved, the photocatalyst has two different structure and property photocatalytic activity centers, and the photocatalytic activity is changed from the energy band structure and the catalytic activity.

This invention discloses a method for preparing a Bi3O4Br catalyst for the efficient degradation of tetracycline, comprising the following steps: S1, mixing bismuth nitrate and potassium bromide in an aqueous solution at room temperature, stirring, and filtering after the reaction to obtain a precipitate; S2, washing and drying the obtained precipitate to obtain a BiOBr precursor; S3, placing the obtained BiOBr precursor in a sodium hydroxide solution of a certain concentration and reacting at a certain temperature to obtain the Bi3O4Br catalyst. Experimental results show that the Bi3O4Br catalyst has a larger specific surface area and more photocatalytic active sites than pure Bi3O4Br, and has a higher oxygen vacancy (OV) concentration, exhibiting high catalytic activity in the photocatalytic degradation of tetracycline. This photocatalyst has broad practical value and application prospects.

The invention discloses a device and method for synthesizing a fourth-generation refrigerant R1235ze through photocatalysis of VDF, and belongs to the technical field of green chemical engineering. The core of the method is that a g-C3N4 / BiVO4 heterojunction photocatalyst is adopted to catalyze VDF to react with hydrogen chloride to generate R1234ze under the mild condition of 70-90 DEG C under the irradiation of simulated sunlight (AM1.5 G). The catalyst is prepared by taking melamine, bismuth nitrate and ammonium metavanadate as precursors and carrying out hydrothermal reaction and calcination treatment under specific conditions. The matched industrial system realizes the whole process integration from the continuous preparation of the catalyst to the online separation of the product. According to the method, the reaction temperature is successfully reduced to about 80 DEG C from traditional 400 DEG C or above, energy consumption is reduced by about 75%, CO2 emission is reduced by about 60%, meanwhile, the product selectivity is not lower than 93%, the quantum efficiency is not lower than 12%, the purity reaches up to 99.5% or above, and a subversive solution is provided for green and low-cost industrial production of R1234ze.